Method of smoke reduction and apparatus therefor

ABSTRACT

Reduction in amount of smoke associated with fuel oil fires in pans for firefighter training purposes is achieved by providing atomized water sprays impinging on the fire just above the layer of burning oil which floats on a body of water in the pan. Water is pumped through spray heads at controlled rates via distribution system immersed in the water beneath the burning oil to prevent generation of steam.

United States Patent Goldsmith [54] METHOD OF SMOKE REDUCTION AND APPARATUS THEREFOR [72] Inventor: AlexnnderGoldsmithChicago,111.

[73] Assignee: The United States of America as represented by the Secretary of the Navy [22} Filed: Nov. 25, 1970 [21] Appl.No.: 92,620

[ 5] Feb. 22, 1972 Primary Examiner-Edward G. Favors Attorney-Richard S. Sciascia, John W. Pease and Harvey A. David ABSTRACT Reduction in amount of smoke associated with fuel oil fires in pans for firefighter training purposes is achieved by providing atomized water sprays impinging on the fire just above the layer of burning oil which floats on .a body of water in the pan. Water is pumped through spray heads at controlled rates via distribution system immersed in the water beneath the burning [56] References Cited oil to prevent generation of steamv UNITED STATES PATENTS 10 Claims, 4 Drawing Figures 774,447 1111904 Muth ..431/4 3,330,231 7/1967 Spencer ..1 10/81 X /fla /6 /5 20 22 24 fl/mp 2 J T SHEET 1 OF 2 PATENTEDFEB22 I972 METHOD OF SMOKE REDUCTION AND APPARATUS THEREFOR I BACKGROUND OF THE INVENTION This invention relates to the reduction of smoke associated with oil fires intentionally set for the purpose of training firefighting personnel.

In the training of men in the fighting of shipboard fires, aircraft crashes, and the like, it has been the practice to float oil on the free surface of an otherwise confined body of water and set it afire. In some instances the area to which the fire is confined is quite large and is out-of-doors or at least not enclosed by wall means about the immediate area. These fires are used for training in the extinguishing of fires such as might occur from aircraft crashes on runways, fires on deck or in other relatively open spaces such as hangars, or the like.

In other instances the fires are set in confined spaces simulative of boiler rooms or the like. This is accomplished at some training sites with actual rooms and at other sites with walls or baffles erected partially or entirely around the fire.

In all of these situations the burning fuel oil creates a conflagration which the trainees can fight with standard equipment including fire hoses equipped with a variety of nozzles including sprays and fogging nozzles. The factors of heat, noise, smoke, visual stimulation, and the characteristic fighting back and jumping" of the fire are all present to lend reality to the training situation including the installation of some degree of fear and apprehension in the trainees.

One of these factors, namely smoke, contributes little by its presence to the training situation. Because many of the training sites now in use are in or near populated areas, and because of the present day awareness and concern about air pollution by smoke, it has become necessary to find ways of substantially reducing the amount of smoke generated by the fires used in training sessions.

SUMMARY OF THE INVENTION With the foregoing in mind it is a principal object of this invention to provide methods and apparatus for materially reducing the amount of smoke generated by an oil fire burning on the free surface of a body of water such as for purposes of training firefighting personnel.

It is another important object of this invention to accomplish the foregoing without otherwise materially changing the character of the trainingfires with respect to heat, noise, fight back,jumping, and visual stimulation.

Still another object of the invention is to provide methods and apparatus which are reliable, inexpensive, and readily installed in new and existing firefighting training facilities.

As another object the invention aims to accomplish the foregoing through the provision of a method which comprises the delivery of predetermined quantities of water to the area or zone of burning, atomizing the water so delivered, and causing the atomized water to impinge on the burning oil.

Yet another object is the provision for conducting water to the zone of burning oil and for atomizing the water and causing it to impinge against the burning oil.

The invention may be further said to reside in certain novel combinations, arrangements of parts, and steps by which the foregoing objects and advantages as well as others are achieved as will become apparent from the following detailed description of the preferred embodiments when read in conjunction with the accompanying drawings.

DESCRIPTION OF THE DRAWINGS FIG. I is a plan view of an open fire simulator embodying the present invention;

FIG. 2 is a sectional view of the apparatus taken substantially along line 2-2 of FIG. 1;

FIG. 3 is a plan fragmentary view of an enclosed fire simulator embodying the invention; and

FIG. 4 is a side-elevational view of the embodiment of FIG.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the form of the invention illustrated in FIGS. I and 2, an open fire simulating device comprises a steel pan I0 which comprises vertical side walls and a bottom wall 10b. The pan 10 may have dimensions appropriate to the size of fire to be simulated, but in the present example will be considered to be a typical square tank of 4 feet by 4 feet presenting l6 square feet of fire area. Larger areas are often used and may be circular or some other shape.

A body of water 12 is confined in the pan I0 and a layer of oil 14 is floated on the free surface of the water with the surface of the oil coming to within a fraction of an inch of the upper edges of the pan. Any suitable fuel oil such as is used for heating, ship propulsion or the like may be used.

In accordance with this invention, a water-spray system is provided and comprises a pressure pump 16 which receives water from a suitable supply via line 18. The pump 16, which is conveniently electrically driven, although pumps driven by other means will suffice, has its output line 20 connected to a rate regulating control valve 22. The discharge pipe or conduit 24 from the valve 22 leads to the interior of the pan 10. A water-distribution system is disposed along the bottom wall 10b of the pan and comprises distributing pipes or conduits 26 connected to the conduit 24. A plurality of risers 28 are connected to the distributing conduits 26, there being in the present example nine such risers spaced on approximately 16 to 18-inch centers.

Mounted on the upper end of each riser 28 is an atomizing spray nozzle 30. The upper ends or tips of these spray nozzles 30 protrude slightly above the surface of the oil 14. The nozzles 30 are preferably of a commercially available variety which emit a hollow cone of fine spray, the cone having a vertex angle x of about A suitable nozzle is available from Spraying Systems Company, 3201 Randolph Street, Bellwood, III.

In the operation of the device, once a fire is well started in the pan 10, the control valve 22 is opened and adjusted to pass the required amount of water driven by the pump 16 through the nozzles 30 to produce the maximum reduction of smoke consistent with continued burning of the oil with the desired characteristics of heat, noise, fight back and jumping ability. It has been determined experimentally that for an open fire simulator, atomized water applied in the above manner at rates from 0.35 lb./min.-sq. ft. to 0.46 lb./min.-sq. ft. produces the desired results, with application rates in the upper portion of the stated range being most effective. Application rates greater than 0.46 lb./min.-sq. ft. for open fire simulating pans appears to quench the fire somewhat and hence diminishes the desired characteristics discussed earlier.

The application of an atomized water spray to the surface of burning fuel oil is very effective in eliminating nearly all the smoke that is generated by such a fire. Visual observation indicates that the water is responsible for altering the combustion process in some manner. Atomized water injection cause a a lighter flame color throughout, and intensely bright spots wherever a water particle impinges on the surface of the fuel. It apparently also causes more complete combustion because little free-carbon (smoke) remains in the flue gases. The nature of the interaction between the water and fuel in the combustion is not known, but the presence of such an interaction is unmistakable. Moreover, the interaction occurs even when the fuel does not have free access to ambient air.

Referring now to FIGS. 3 and 4 there is illustrated an enclosed fire simulator device which differs from that described with reference to FIGS. 1 and 2 in that the tank 10 is at least partially surrounded by vertical panels or walls 40. These walls, which in actual tests were about 7 feet high, restrict air movement into the zone of a fire in the pan as would be the case in a boiler room fire, for example. The walls 40 define an opening at 42 to simulate a doorway. Oil burning on the surface of water in the pan 10 produces a vigorous fire with fire whirls on either side of the open doorway 42, and a greater burning rate than a fire from an open pan device.

When burning without the benefit of atomized water injection from nozzles the fire produced copious amounts of dense black smoke. With the water spray operating at a rate of 0.94 lb./min.sq. ft. the quantity of smoke from this enclosed fire was substantially reduced and good results were obtained. From experimentation a range of water application of from about 0.50 lb./min.sq. ft. to about 1.0 lb./min.-sq. ft. depending upon the degree of fire enclosure will provide a satisfactory degree of smoke abatement while preserving the desired characteristics of a real situation fire.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

What is claimed is:

l. A method of providing an oil fire for training fire fighters, which fire is characterized by little smoke, said method comprising the steps of:

providing a confined body of water presenting a free surface;

floating a layer of fuel oil on said free surface; igniting said fuel oil;

directing atomized water at the resulting fire above said fuel oil at a rate of from 0.35 lb./min.-sq. ft to 1.0 lb./min.-sq. ft.

2 A method as defined in claim 1 and wherein:

said atomized water is in the form of a plurality of conical sprays each having a vertex angle of about 155 to 165.

3. A method as defined in claim 2 and wherein:

said atomized water is sprayed at a temperature sufficiently below the boiling point thereof so as to prevent flashing into steam before impinging on partially burned hydrocarbons.

4. Apparatus for use in training personnel in fighting fires,

said apparatus comprising:

means for confining a body of water with a free surface;

a layer of fuel oil floating on said surface;

pump means for providing water at elevated pressures;

control valve means connected to the output of said pump means for regulating flow therefrom;

water conduit means connected to said control valve means and leading to the interior of said pan adjacent the bottom thereof;

water-distribution means leading from said conduit means to a plurality of locations near said surface; and

a plurality of spray nozzles connected to said distribution means at said locations, said nozzles having their upper, spray-discharging ends protruding above said layer of oil 5. Apparatus as defined in claim 4, and wherein:

said spray nozzles are characterized by a spray distribution in a hollow, inverted cone with a vertex angle of about 6. Apparatus as defined in claim 4, and further comprising:

vertical wall means disposed around at least a portion of said pan and extending above said pan to at least partially enclose a fire therein.

7. Apparatus as defined in claim 5, and further comprising:

vertical wall means disposed around at least a portion of said pan and extending above said pan to at least partially enclose a fire therein.

8. Apparatus as defined in claim 5, and wherein said distribution means comprises:

pipe means extending laterally from said conduit means;

and

risers extending vertically from said conduit means and pipe means;

said nozzles being connected to the upper ends of said risers.

9. Apparatus as defined in claim 5, and wherein:

said pump means and said control valve means are operable to pass water through said nozzles at a rate of from 0.35 lb./min.-sq. ft. to 0.46 lb./min.-sq. ft.

10 Apparatus as defined in claim 6, and wherein: said pump means and said control valve means are operable to pass water through said nozzles at a rate of from about 0.50 lb./min.-sq. ft. to about 1.0 lb./min.-sq. ft. 

2. A method as defined in claim 1 and wherein: said atomized water is in the form of a plurality of conical sprays each having a vertex angle of about 155* to 165*.
 3. A method as defined in claim 2 and wherein: said atomized water is sprayed at a temperature sufficiently below the boiling point thereof so as to prevent flashing into steam before impinging on partially burned hydrocarbons.
 4. Apparatus for use in training personnel in fighting fires, said apparatus comprising: means for confining a body of water with a free surface; a layer of fuel oil floating on said surface; pump means for providing water at elevated pressures; control valve means connected to the output of said pump means for regulating flow therefrom; water conduit means connected to said control valve means and leading to the interior of said pan adjacent the bottom thereof; water-distribution means leading from said conduit means to a plurality of locations near said surface; and a plurality of spray nozzles connected to said distribution means at said locations, said nozzles having their upper, spray-discharging ends protruding above said layer of oil.
 5. Apparatus as defined in claim 4, and wherein: said spray nozzles are characterized by a spray distribution in a hollow, inverted cone with a vertex angle of about 160*.
 6. Apparatus as defined in claim 4, and further comprising: vertical wall means disposed around at leAst a portion of said pan and extending above said pan to at least partially enclose a fire therein.
 7. Apparatus as defined in claim 5, and further comprising: vertical wall means disposed around at least a portion of said pan and extending above said pan to at least partially enclose a fire therein.
 8. Apparatus as defined in claim 5, and wherein said distribution means comprises: pipe means extending laterally from said conduit means; and risers extending vertically from said conduit means and pipe means; said nozzles being connected to the upper ends of said risers.
 9. Apparatus as defined in claim 5, and wherein: said pump means and said control valve means are operable to pass water through said nozzles at a rate of from 0.35 lb./min.-sq. ft. to 0.46 lb./min.-sq. ft.
 10. Apparatus as defined in claim 6, and wherein: said pump means and said control valve means are operable to pass water through said nozzles at a rate of from about 0.50 lb./min.-sq. ft. to about 1.0 lb./min.-sq. ft. 